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[PMID]: 25716876
[Au] Autor:Pratt RB; MacKinnon ED; Venturas MD; Crous CJ; Jacobsen AL
[Ad] Address:Department of Biology, California State University, Bakersfield, 9001 Stockdale Hwy, Bakersfield, CA 93311, USA rpratt@csub.edu....
[Ti] Title:Root resistance to cavitation is accurately measured using a centrifuge technique.
[So] Source:Tree Physiol;35(2):185-96, 2015 Feb.
[Is] ISSN:1758-4469
[Cp] Country of publication:Canada
[La] Language:eng
[Ab] Abstract:Plants transport water under negative pressure and this makes their xylem vulnerable to cavitation. Among plant organs, root xylem is often highly vulnerable to cavitation due to water stress. The use of centrifuge methods to study organs, such as roots, that have long vessels are hypothesized to produce erroneous estimates of cavitation resistance due to the presence of open vessels through measured samples. The assumption that roots have long vessels may be premature since data for root vessel length are sparse; moreover, recent studies have not supported the existence of a long-vessel artifact for stems when a standard centrifuge technique was used. We examined resistance to cavitation estimated using a standard centrifuge technique and compared these values with native embolism measurements for roots of seven woody species grown in a common garden. For one species we also measured vulnerability using single-vessel air injection. We found excellent agreement between root native embolism and the levels of embolism measured using a centrifuge technique, and with air-seeding estimates from single-vessel injection. Estimates of cavitation resistance measured from centrifuge curves were biologically meaningful and were correlated with field minimum water potentials, vessel diameter (VD), maximum xylem-specific conductivity (Ksmax) and vessel length. Roots did not have unusually long vessels compared with stems; moreover, root vessel length was not correlated to VD or to the vessel length of stems. These results suggest that root cavitation resistance can be accurately and efficiently measured using a standard centrifuge method and that roots are highly vulnerable to cavitation. The role of root cavitation resistance in determining drought tolerance of woody species deserves further study, particularly in the context of climate change.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1093/treephys/tpv003

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[PMID]: 25648379
[Au] Autor:Coskunfirat N; Hadimioglu N; Ertug Z; Akbas H; Davran F; Ozdemir B; Aktas Samur A; Arici G
[Ad] Address:Anesthesiology and Reanimation Department, Antalya, Turkey. Electronic address: nesildgr@yahoo.com....
[Ti] Title:Homocysteine levels after nitrous oxide anesthesia for living-related donor renal transplantation: a randomized, controlled, double-blind study.
[So] Source:Transplant Proc;47(2):313-8, 2015 Mar.
[Is] ISSN:1873-2623
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:BACKGROUND: Nitrous oxide anesthesia increases postoperative homocysteine concentrations. Renal transplantation candidates present with higher homocysteine levels than patients with no renal disease. We designed this study to investigate if homocysteine levels are higher in subjects receiving nitrous oxide for renal transplantation compared with subjects undergoing nitrous oxide free anesthesia. METHODS: Data from 59 patients scheduled for living-related donor renal transplantation surgery were analyzed in this randomized, controlled, blinded, parallel-group, longitudinal trial. Patients were assigned to receive general anesthesia with (flowmeter was set at 2 L/min nitrous oxide and 1 L/min oxygen) or without nitrous oxide (2 L/min air and 1 L/min oxygen). We evaluated levels of total homocysteine and known determinants, including creatinine, folate, vitamin B12, albumin, and lipids. We evaluated factor V and von Willebrand factor (vWF) to determine endothelial dysfunction and creatinine kinase myocardial band (CKMB)-mass, troponin T to show myocardial ischemia preoperatively in the holding area (T1), after discontinuation of anesthetic gases (T2), and 24 hours after induction (T3). RESULTS: Compared with baseline, homocysteine concentrations significantly decreased both in the nitrous oxide (22.3 ± 16.3 vs 11.8 ± 9.9; P < .00001) and nitrous oxide-free groups (21.5 ± 15.3 vs 8.0 ± 5.7; P < .0001) at postoperative hour 24. The nitrous oxide group had significantly higher mean plasma homocysteine concentrations than the nitrous oxide-free group (P = .021). The actual homocysteine difference between groups was 3.8 µmol/L. CONCLUSION: This study shows that homocysteine levels markedly decrease within 24 hours after living-related donor kidney transplantation. Patients receiving nitrous oxide have a lesser reduction, but this finding is unlikely to have a clinical relevance.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review

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[PMID]: 25768179
[Au] Autor:Liu T; Yin J; Jiang J; Liu K; Wang S; Zou S
[Ti] Title:Differential-pressure-based fiber-optic temperature sensor using Fabry-Perot interferometry.
[So] Source:Opt Lett;40(6):1049-52, 2015 Mar 15.
[Is] ISSN:1539-4794
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:We propose a novel fiber-optic Fabry-Perot interferometric (FFPI) temperature sensor based on differential pressure resulting from thermal expansion of sealed air. A thin silicon diaphragm is sandwiched between two micro-circular cavity-structured Pyrex plates to construct a FP and an air cavity. The thermal expansion of sealed air induces differential pressure variation between cavities and thus the deformation of thin diaphragm, which transfers temperature change into cavity length shift of FP interferometer. Theory analysis results indicate that the temperature-sensitivity can be designed flexibly by choosing the parameters of radius and thickness of silicon diaphragm, and the differential pressure between two cavities. Experimental results demonstrate that the temperature sensitivity of 6.07 nm/°C is achieved with the resolution of 0.10°C under the range of -50°C to 100°C, and the response time is around 1.3 s with temperature change from 28°C to 100°C.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1364/OL.40.001049

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[PMID]: 25768171
[Au] Autor:Qiu X; Zhang Z; Xie L; Qiu J; Gao F; Du J
[Ti] Title:Incident-polarization-sensitive and large in-plane-photonic-spin-splitting at the Brewster angle.
[So] Source:Opt Lett;40(6):1018-21, 2015 Mar 15.
[Is] ISSN:1539-4794
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:In this Letter, we report a phenomenon of large in-plane-photonic-spin-splitting (IPPSS) in the case of a linear polarized Gaussian light beam reflected from an air-glass interface at the Brewster angle. The IPPSS-induced displacement reaches ∼12.4 µm, which is quite larger than the previously reported value. Particularly, the IPPSS is extremely sensitive (∼70 µm/deg) to the incident polarization. We also find that the direction of the spin accumulation can be switched by adjusting the incident polarization slightly. These findings may have useful applications in spin manipulation and precise polarization metrology.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1364/OL.40.001018

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[PMID]: 25768170
[Au] Autor:Spokoyny B; Koh CJ; Harel E
[Ti] Title:Stable and high-power few cycle supercontinuum for 2D ultrabroadband electronic spectroscopy.
[So] Source:Opt Lett;40(6):1014-7, 2015 Mar 15.
[Is] ISSN:1539-4794
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Broadband supercontinuum (SC) pulses in the few cycle regime are a promising source for spectroscopic and imaging applications. However, SC sources are plagued by poor stability, greatly limiting their utility in phase-resolved nonlinear experiments such as 2D photon echo spectroscopy (2D PES). Here, we generated SC by two-stage filamentation in argon and air starting from 100 fs input pulses, which are sufficiently high-power and stable to record time-resolved 2D PE spectra in a single laser shot. We obtain a total power of 400 µJ/pulse in the visible spectral range of 500-850 nm and, after compression, yield pulses with duration of 6 fs according to transient-grating frequency-resolved optical gating (TG-FROG) measurements. We demonstrate the method on the laser dye, Cresyl Violet, and observe coherent oscillations indicative of nuclear wavepacket dynamics.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1364/OL.40.001014

  6 / 267373 MEDLINE  
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[PMID]: 25768168
[Au] Autor:Singh D; Dasgupta A; Aswathy VG; Tripathi RP; Pavan Kumar GV
[Ti] Title:Directional out-coupling of light from a plasmonic nanowire-nanoparticle junction.
[So] Source:Opt Lett;40(6):1006-9, 2015 Mar 15.
[Is] ISSN:1539-4794
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:We experimentally show how a single Ag nanoparticle (NP) coupled to an Ag nanowire (NW) can convert propagating surface plasmon polaritons to directional photons. By employing dual-excitation Fourier microscopy with spatially filtered collection-optics, we show single- and dual-directional out-coupling of light from NW-NP junction for plasmons excited through glass-substrate and air-superstrate. Furthermore, we show NW-NP junction can influence the directionality of molecular-fluorescence emission, thus functioning as an optical antenna. The results discussed herein may have implications in realizing directional single-photon sources and quantum plasmon circuitry.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1364/OL.40.001006

  7 / 267373 MEDLINE  
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[PMID]: 25768151
[Au] Autor:Kehlet LM; Tidemand-Lichtenberg P; Dam JS; Pedersen C
[Ti] Title:Infrared upconversion hyperspectral imaging.
[So] Source:Opt Lett;40(6):938-41, 2015 Mar 15.
[Is] ISSN:1539-4794
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:In this Letter, hyperspectral imaging in the mid-IR spectral region is demonstrated based on nonlinear frequency upconversion and subsequent imaging using a standard Si-based CCD camera. A series of upconverted images are acquired with different phase match conditions for the nonlinear frequency conversion process. From this, a sequence of monochromatic images in the 3.2-3.4 µm range is generated. The imaged object consists of a standard United States Air Force resolution target combined with a polystyrene film, resulting in the presence of both spatial and spectral information in the infrared image.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1364/OL.40.000938

  8 / 267373 MEDLINE  
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[PMID]: 25672612
[Au] Autor:Kang DG; Park SI; Kim SH; Chung MJ; Lee KM; Lee JH
[Ad] Address:Department of Radiation Oncology, St Vincent's Hospital, the Catholic University of Korea, 93, Ji-dong, Paldal-gu, Suwon, Gyeonggi-do, Korea Department of Biomedical Engineering, Electronic Engineering, Jeju National University of Korea, Jeju-si, Jeju Special Self-Governing Province, Korea....
[Ti] Title:Evaluation of the Flash effect in breast irradiation using TomoDirect: an investigational study.
[So] Source:J Radiat Res;56(2):397-404, 2015 Mar.
[Is] ISSN:1349-9157
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:Flash is a specified function in TomoDirect that enables beam expansion by opening additional leaves to the target. This study assessed the theoretical dose distribution resulting from Flash in breast irradiation using TomoDirect. A cylindrical phantom that enabled dose distribution of the breast was used for verifying the effect of planning target volume (PTV) contouring and Flash. A total of 18 Gy in 10 fractions were prescribed to the PTV. Five PTVs were then created by Contracting this contour by 0, 1, 2, 3, 4 and 5 mm, giving PTV-x. Flash ±x is defined by opening x (number) of the leaves. The Flash effect in the air was compared with each set-up error of 5, 10 and 15 mm, respectively. The minimum PTV dose from PTV-1 to PTV-3 increased from 13.88 Gy to 15.86 Gy. In contrast, Dmin in PTV-4 and PTV-5 was 17.80 Gy in 98.88% of the prescription dose. Without Flash, when 5-, 10- and 15-mm set-up errors applied in the PTV, relative doses of 87.88, 23.73 and 7.94% were observed, respectively. However, in Flash 3, which was equal to the usual air margin of 1.875 cm, a relative dose of 104.24% ± 0.30% was observed, irrespective of set-up errors (5 mm to 15 mm). Flash opening is useful for countervailing set-up errors in breast cancer patients who receive breast irradiation with TomoDirect.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1093/jrr/rru118

  9 / 267373 MEDLINE  
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[PMID]: 25768814
[Au] Autor:Kothapalli SV; Daeichin V; Mastik F; Brodin LA; Janerot-Sjoberg B; Paradossi G; de Jong N; Grishenkov D
[Ti] Title:Unique pumping-out fracturing mechanism of a polymer-shelled contrast agent: an acoustic characterization and optical visualization.
[So] Source:IEEE Trans Ultrason Ferroelectr Freq Control;62(3):451-62, 2015 Mar.
[Is] ISSN:1525-8955
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:This work describes the fracturing mechanism of air-filled microbubbles (MBs) encapsulated by a cross-linked poly(vinyl alcohol) (PVA) shell. The radial oscillation and fracturing events following the ultrasound exposure were visualized with an ultrahigh-speed camera, and backscattered timedomain signals were acquired with the acoustic setup specific for harmonic detection. No evidence of gas emerging from defects in the shell with the arrival of the first insonation burst was found. In optical recordings, more than one shell defect was noted, and the gas core was drained without any sign of air extrusion when several consecutive bursts of 1 MPa amplitude were applied. In acoustic tests, the backscattered peak-to-peak voltage gradually reached its maximum and exponentially decreased when the PVA-based MB suspension was exposed to approximately 20 consecutive bursts arriving at pulse repetition frequencies of 100 and 500 Hz. Taking into account that the PVA shell is porous and possibly contains large air pockets between the cross-linked PVA chains, the aforementioned acoustic behavior might be attributed to pumping gas from these pockets in combination with gas release from the core through shell defects. We refer to this fracturing mechanism as pumping-out behavior, and this behavior could have potential use for the local delivery of therapeutic gases, such as nitric oxide.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1109/TUFFC.2014.006732

  10 / 267373 MEDLINE  
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[PMID]: 25768812
[Au] Autor:Sadiq M; Kuang Y; Cochran S; Huang Z
[Ti] Title:High-performance planar ultrasonic tool based on d31-mode piezocrystal.
[So] Source:IEEE Trans Ultrason Ferroelectr Freq Control;62(3):428-38, 2015 Mar.
[Is] ISSN:1525-8955
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Ultrasonic scalpels based on the conventional mass-spring configuration of piezoelectric transducers are widely used in procedures such as oral, hepatic, and pancreatic surgery. However, the weight and self-heating of this configuration are weaknesses. To address these, an alternative approach can be adopted which utilizes a planar configuration of a cutting blade to which piezoelectric drive components are bonded directly. This paper details the design and characterization of three such planar scalpels, made of surgical-grade stainless steel and silicon. These tools operate in the d31 mode configuration, utilizing relaxor-PT single-crystal binary (PMN-PT) and manganese-doped ternary (Mn:PIN-PMN-PT) composition piezoelectric materials. The scalpels, with shapes resembling a dagger, are able to produce longitudinal displacements >5 µm when driven with 20 Vp-p at their respective resonant frequencies, 73 and 106 kHz. It is observed that both blade and piezoelectric materials significantly affect the performance of the planar tool. The mechanical quality factor, QM, of PMNPT based silicon tool is ~1500 in air compared with ~350 for its stainless steel counterpart, and the use of Mn:PIN-PMNPT further increases the QM to ~2400. Furthermore, the study on the effect of various tissue-loading conditions suggest that skin is the most difficult tissue to penetrate, consequently leading to significant reduction in the tool's efficiency and therefore demanding high-QM tools.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1503
[Js] Journal subset:IM
[St] Status:In-Data-Review
[do] DOI:10.1109/TUFFC.2014.006437


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